1. This study requires a total of 15 visits, broken down by the following: 1 baseline visit, 3 MRI visits, 10 tDCS testing visits, and 1 final follow-up/debriefing visit. Patient participant will last for a total of 5 consecutive weeks. During this time, we will be collecting clinical and psycophysical evaluation: the MRI photo imaging, DNIC/MAST pain tolerance data (computerized), and pain questionnaires (verbal), Quantitative Sensory Test (QST).